ByRochelle Jenks:In August, 2012, the government published the 2025 standards for automakers. The Corporate Average Fuel Economy (CAFE) standards require the average fuel efficiency of new cars and trucks to be 54.5 miles per gallon.

Cars averaging 23.8 mpg don't usually get much coverage on GreenCarReports — they simply aren't that green. In this instance though, that gas mileage figure doesn't refer to a particular car — it refers to every car sold in 2012.

Audi’s best-selling sport utility vehicle, the Q5, gets even better in 2014 with the addition of a six-cylinder, diesel engine that is fuel-thrifty yet muscular. The federal government mileage ratings for the new-for-2014 Q5 TDI with turbocharged and direct-injection V-6 — 24 miles per gallon in city driving and 31 mpg on highways — rival those of many SUVs with smaller, four-cylinder, gasoline engines. It’s even rated 1 mpg more in highway driving than the gasoline-electric hybrid Audi Q5.

Audi’s best-selling sport utility vehicle, the Q5, gets even better in 2014 with the addition of a six-cylinder, diesel engine that is fuel-thrifty yet muscular. The federal government mileage ratings for the new-for-2014 Q5 TDI with turbocharged and direct-injection V-6 — 24 miles per gallon in city driving and 31 mpg on highways — rival those of many SUVs with smaller, four-cylinder, gasoline engines. It’s even rated 1 mpg more in highway driving than the gasoline-electric hybrid Audi Q5.

In July 2011, the Obama administration announced the new Corporate Average Fuel Economy (CAFE) standards that will begin taking effect in 2017. The standards for U.S. light-duty vehicle fleets (passenger vehicles and light-duty trucks) will be 54.5 miles per gallon (mpg) by 2025, and they piggyback on the 2009 mandate for a CAFE average of 35.5 mpg by 2016, up from 27.3 mpg in 2011.